Free light chains (serum)

 

Alternative names, keywords

Kappa, lambda, FLC, SFLC

Samples required

● Clotted blood (gold cap, 5 mL tube).

Test indications

For the investigation of possible paraproteinaemia, which can be present in multiple myeloma, lymphoma, Waldenstrom macroglobulinaemia etc.

Please request serum free light chains WITH serum protein electrophoresis for a full paraprotein screen.

Reference range

Kappa: 3 - 19 mg/L
Lambda: 6 - 26 mg/L
Kappa:lambda ratio: 0.26 - 1.65

 

Note new reference ranges from 1 July 2026:

  Kappa free light chain (mg/L) Lambda free light chain (mg/L) Serum free light chain ratio

eGFR ≥60:

less than 70 years

 6.3 - 39.0 5.9 - 36.7 0.44 - 2.16

70 years and above

 7.0 - 55.8 6.4 - 48.0 0.46 - 2.59

eGFR 45 - 59*

 7.8 - 83.6 7.3 - 65.1
less than 70 years: 0.44 - 2.16
70 years and above: 0.46 - 2.59

eGFR 30 - 44*

 8.8 - 103.3 8.2 - 73.2

eGFR less than 30*

 11.7 - 265.1 12.6 - 150.9

* eGFR-specific reference ranges for kappa and lambda may not be specified on the report. The reference ranges for the ratio do not change based on eGFR.

 

Turnaround time

2 working days

Enquiries

Biochemistry (Special Chemistry)

 

Details